1. Field of the Invention
The present invention relates to a training manikin for practising external cardiac massage, including chest expansion, comprising a partially compressible chest. In particular, the invention relates to a training manikin for practising CPR (cardiopulmonary resuscitation) techniques.
2. The Prior Art
Cardiac arrest, which is a frequent cause of death, can arise from a stoppage of breathing e.g., in case of drowning accidents, electrical shocks or diseases, such as arteriosclerosis, cardiac infarct and cardiac block.
The treatment of cardiac arrest comprises resuscitation treatments including i.a., cardiac massage. When performing external cardiac massage, the patient is placed on a solid support, and the person performing the cardiac massage kneels by the side of the patient's chest and applies rhytmical pressures on the patient's sternum with the palm of his hand. A cardiac arrest is normally accompanied by respiratory arrest, and, therefore, it is necessary to administer artifical respiration in connection with the cardiac massage.
CPR resuscitation techniques, i.e., techniques comprising both cardiac massage and artifical respiration, are widely used by rescuers and doctors, but as an incorrect cardiac massage may cause injury to the patient, there is a need for thoroughly practising at these techniques.
For this purpose a variety of training manikins have been devised. Such a training manikin is disclosed in U.S. Pat. No. 4,984,987. This prior art training manikin comprises a head having a mouth and a neck portion connected with the oral cavity on the one side and a lung device on the other side. The lung device is in the form of an inflatable bag located in the chest comprising a front plate, a rear plate and an intervening compressible bag.
When using the prior art training manikin, artifical respiration is practised by blowing air into the mouth of the manikin, from which it flows into the inflatable bag which, when inflated, exerts a pressure on the front plate of the chest, thereby causing the chest to rise.
The practising of an artificial respiration is alternated at intervals with the practising of cardiac massage, which is effected by exerting a vertical pressure on the front plate of the chest so that it moves towards the rear plate under simultaneous compression of the bag. When the pressure ceases, the bag causes the front plate to return to its starting position.
Recently it has been found that the effect of cardiac massage is increased if the cardiac compression and the subsequent release of pressure, during which the chest resumes its original volume, is supplemented with a chest expansion caused by an upward pull. Such a chest expansion has been found to produce increased blood circulation and lung ventilation.
The chest expansion can be performed by using a pull member in the form of a resilient suction cup. When the pull member is pressed against the chest, the suction cup becomes deformed, thereby squeezing out the air. When the pressure on the suction cup ceases, the suction cup will try to resume its original configuration, and as a result thereof a vacuum is created in the interior of the suction cup. Further pulling of the suction cup increases the vacuum, thus causing the pull member to be strongly attached to the chest.
In order to facilitate transport and storage, the prior art training manikins for practising cardiac massage and optionally artifical respiration are relatively light, and therefore chest expansion on such training manikins cannot be performed unless they are attached to a support, e.g., a floor. However, such attachment will make it difficult to use the training manikin, and hence the manikin can only be used in places allowing such attachment.